About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Defects and Interfaces: Modeling and Experiments
|
Presentation Title |
Alloy Effects on Grain Boundary Kinetics and Disconnection Nucleation |
Author(s) |
Spencer L. Thomas, Jason Trelewicz |
On-Site Speaker (Planned) |
Spencer L. Thomas |
Abstract Scope |
Disconnections are grain boundary (GB) dislocations that mediate GB migration and sliding/creep. Grain boundaries can absorb lattice dislocations in the form of disconnections, meaning that an understanding of disconnections is essential to understanding the role of GBs in scavenging defects arising from deformation and radiation damage. These effects are more pronounced in fine-grained systems due to the higher density of GBs, but such systems are generally stabilized with the addition of segregating solutes. The introduction of solutes alters the energetics of disconnections and, in turn, the behaviors of GBs in ways that are impossible to predict without considering the disconnection mechanism. We present an atomistic study on disconnection nucleation, showing that addition of Cu or Al to Ni GBs reduces disconnection nucleation barriers. We show via theory, Kinetic Monte Carlo, and Molecular Dynamics that this barrier reduction enhances the effective GB mobility and the efficiency with which GBs accommodate stress. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Mechanical Properties |